Warning sign



5. Warning sign

5.1 : Front

5.2 : Back

5.3 : Top

5.4 : Right

The left view is omitted because it is identical with the right view; the bottom view is omitted because it is identical with the top view; the dot-dash broken lines define the boundaries of the claimed design and form no part of the claimed design; the broken lines inside the boundaries form part of the claimed design; any other broken lines illustrate portions of the warning sign and form no part of the claimed design. 

CLAIM The ornamental design for a warning sign, as shown and described. 